Synergistic preservative compositions

Abstract

What is described herein is a synergistic preservative composition capable of providing broad spectrum antimicrobial activity comprising: (i) about 0.1 wt. % to about 99.9 wt. % of propylene carbonate; (ii) about 0.1 wt. % to about 99.9 wt. % of one or more organic compounds, and wherein, inclusion of each additional organic compound is capable of demonstrating cumulative synergistic effect; and (iii) optionally about 0.1 wt. % to 99.0 wt. % of one or more preservative compounds, and wherein, inclusion of each preservative compound is capable of demonstrating cumulative synergistic effect, wherein the Synergy Index (SI) value of the total composition is from about 0.05 to about 0.95. Also described is a process for preparing said composition and method of use of the same.

What is claimed is: 
     
         1 . A synergistic preservative composition capable of providing broad spectrum antimicrobial activity comprising:
 i. about 0.1 wt. % to about 99.9 wt. % of propylene carbonate;   ii. about 0.1 wt. % to about 99.9 wt. % of one or more organic compounds, and wherein, inclusion of each additional organic compound is capable of demonstrating cumulative synergistic effect; and   iii. optionally about 0.1 wt. % to 99.0 wt. % of one or more preservative compounds, and wherein, inclusion of each preservative compound is capable of demonstrating cumulative synergistic effect,   
       wherein the Synergy Index (SI) value of the total composition is from about 0.05 to about 1.0. 
     
     
         2 . The preservative composition according to  claim 1 , wherein the synergy index (SI) values of the composition is from about 0.05 to 0.96. 
     
     
         3 . The preservative composition according to  claim 1 , wherein said cumulative synergy increases the efficacy of the total composition and reduces the required antimicrobial use levels of said (i) one or more organic compounds and/or (ii) one or more preservative compounds. 
     
     
         4 . The preservative composition according to  claim 1 , wherein the inclusion of propylene carbonate to a said (i) one or more organic compound/s and/or (ii) one or more preservative compound/s provides an effective composition capable of demonstrating cumulative synergism. 
     
     
         5 . The preservative composition according to  claim 1 , wherein said (i) one or more organic compound/s and/or (ii) one or more preservative compound/s are selected based on their Synergy Index ranging from about 0.10 to about 0.96 to provide cumulative synergy. 
     
     
         6 . The preservative composition accordingly  claim 1 , wherein said organic compounds are selected from the group consisting of diols, C 2 -C 20  alkane diols, glycerins, C 4 -C 18  alkyl glycerins, esters of glycerins, organic acids and their sodium/potassium salts, C 2 -C 20  fatty acids and their sodium/potassium salts, esters of organic acids, esters of C 2 -C 20  fatty acids, waxes, terpenes, triglycerides, protein acids, amino peptides, oligo peptides, aromatic aldehydes, glucosides, enzymes, peptides/amino acid and their esters, essential oils, natural preservatives, herbal preservatives, and/or oils derived from natural products. 
     
     
         7 . The preservative composition according to  claim 6 , wherein the organic acid is selected from the group consisting of sugar acids, α-hydroxy carboxylic acids, β-hydroxy carboxylic acids, α-hydroxy organic acids and/or β-hydroxy organic acids. 
     
     
         8 . The preservative composition according to  claim 6 , wherein the fatty acid is selected from the group consisting of saturated fatty acids, or unsaturated fatty acids. 
     
     
         9 . The preservative composition according to  claim 1 , wherein said synergistic preservative composition is selected from the group consisting of:
 i. (a) propylene carbonate with (b) octanediol/decanediol/hexanediol;   ii. (a) propylene carbonate with (b) hexylglycerin/cyclohexyl glycerin;   iii. (a) a mixture of propylene carbonate and hexylglycerin/cyclohexyl glycerin with (b) octanediol/decanediol/hexanediol;   iv. (a) a mixture of propylene carbonate and octanediol/decanediol/hexanediol with (b) hexylglycerin/cyclohexyl glycerins;   v. (a) a mixture of propylene carbonate, octanediol, decanediol, water, salicylaldehyde, and undecanal; and   vi. (a) a mixture of propylene carbonate and cyclohexylglycerin/hexanediol/octanediol with (b) sorbic acid and their alkali metal salts, salicylic acid and their alkali metal salts, or octanoic acid and their alkali metal salts.   
     
     
         10 . The preservative composition according to  claim 1 , wherein said preservative or preservative system comprises at least one preservative compound selected from the group consisting of triclosan, 2-methyl-4-isothiazolin-3-one (MIT), 1,2-benzisothiazolin-3-one (BIT), 5-chloro-2-methyl-4-isothiazolin-3-one (CMIT), 2-octyl-4-isothiazolin-3-one (OIT), 3-iodo-2-propynylbutyl-carbamate (IPBC), 3-iodopropynyl-N-phenyl carbamate (IPPC), zinc pyrithione (ZnPy), bronopol, quaternary ammonium compounds, parabens, alkyl parabens, chlorophenisin, benzyl alcohol, organic acids, sorbic acid and their salts, benzoic acid and their salts, salicylic and their salts, potassium sorbate, sodium benzoate, phenoxyethanol, diazolidinyl urea, imidazolidinyl urea, sodium hydroxymethyl glycinate, hydantoins, sodium pyrithione, phenyl ethanol, phenyl propanol, benzalkonium quaternary ammonium compounds, fatty acids and their salts, α-hydroxy acids and their salts, beta acids and their salts, glycerols, hexyl glycerine, tropolones, sisquiterpenes, and/or ethyl hexyl glycerine. 
     
     
         11 . The preservative composition according to  claim 1 , wherein said composition is capable of inhibiting or killing yeasts, mold spores, gram (+), gram (−) bacterial strains, acne causing strains, odor causing strains, or mycoses causing strains. 
     
     
         12 . The preservative composition according to  claim 1 , wherein said composition is capable of inhibiting or killing  Candida tropicalis, Candida albicans, Hansenula anomala, Saccharomyces cerevisiae, Torulaspora delbreuckii, Zygosaccharomyces bailii, Zygosaccharomyces rouxii, Bacillus subtilis, Bacillus cereus, Staphylococcus aureus, Staphylococus epidermidis, Escherichia coli, Salmonella typhimurium, Salmonella enteritidis, Pseudomonas aeruginosa, Aspergillus niger, Aspergillus flavus, Penicillium islandicum, Penicillium citrinum, Penicillium chrysogenum, Fusarium oxysporum, Fusarium graminearum, Fusarium solani, Alternaria alternata, Aspergillus brasiliensis, Burkhodelia cepacia, Enterobacter aerogenes, Enterobacter cloacae, Enterobacter gergoviae, Klebsiella pneumoniae, Proteus vulgaris, Pseudomonas fluorescens, Pseudomonas putida, Penicillium pinophilum  and/or  Mucor racemosus.    
     
     
         13 . The preservative composition according to  claim 1 , wherein said composition is stable on storage for at least 2 years at room temperature. 
     
     
         14 . The preservative composition according to  claim 1 , wherein said composition is aqueous or non-aqueous in nature. 
     
     
         15 . The preservative composition according to  claim 1 , wherein said composition is delivered as an emulsion, microemulsion, nanoemulsion, solution, dispersion, suspension, complex coacervate, lamellar based delivery system, liposome/niosome formulation, or concentrate. 
     
     
         16 . The preservative composition according to  claim 1  employed in aqueous and non-aqueous based end-user applications comprising cosmetic products, toiletry products, personal care products, oral care products, skin care products, hair care products, household & cleaning products, soap and bath products, industrial and institutional cleaning products, disinfecting products, wound care, sanitary products, agricultural compositions, textile industries, coating industries and/or laundry products. 
     
     
         17 . The preservative composition according to  claim 1 , wherein the amount of preservative composition employed in aqueous and non-aqueous based end-user products/compositions is in the range of from about 0.01 wt. % to about 5.0 wt. % of the total composition. 
     
     
         18 . A process for preparing the synergistic preservative composition of  claim 1 , wherein said process comprises mixing (i) about 0.1 wt. % to about 99.9 wt. % of propylene carbonate; (ii) about 0.1 wt. % to about 99.9 wt. % of one or more organic compounds selected from the group consisting of diols, C 2 -C 20  alkane diols, glycerins, C 4 -C 18  alkyl glycerins, esters of glycerins, organic acids and their sodium/potassium salts, C 2 -C 20  fatty acids and their sodium/potassium salts, esters of organic acids, esters of C 2 -C 20  fatty acids, waxes, terpenes, triglycerides, amino acids, protein acids, amino peptides, oligo peptides, essential oils, natural preservatives, herbal preservatives, and/or oils derived from natural products; and (iii) optionally about 0.1 wt. % to 99.0 wt. % of one or more preservatives to provide homogenous solution. 
     
     
         19 . A synergistic preservative composition capable of providing broad spectrum antimicrobial activity comprising:
 i. about 0.1 wt. % to about 99.9 wt. % of propylene carbonate;   ii. about 0.1 wt. % to about 99.9 wt. % of one or more organic compounds selected from the group consisting of diols, alkane diols, glycerins, alkyl glycerins, esters of glycerins, organic acids and their salts, fatty acids and their salts, and/or esters of long chain fatty acids; and   iii. optionally about 0.1 wt. % to 20.0 wt. % of one or more preservatives.   
     
     
         20 . A synergistic preservative composition capable of providing broad spectrum antimicrobial activity comprising:
 i. about 0.1 wt. % to about 99.9 wt. % of propylene carbonate;   ii. about 0.1 wt. % to about 99.9 wt. % of one or more organic compounds selected from the group consisting of propanediol, hexanediol, octanediol, decanediol, hexylglycerin, cyclohexylglycerin, glyceryl mono-di caprylate, propylene mono-di caprylate, octanoic acid and its sodium salts, methyl propane diol, glyceryl caprylate, propylene glycol monoheptanoate, glycerol monolaurate; and   iii. optionally about 0.1 wt. % to 20.0 wt. % of one or more preservative is selected from the group consisting of salicylic acid, sodium salicylate, sorbic acid, potassium sorbate, dehydroacetic acid (DHA), benzoic acid, sodium benzoate, cinnamaldehyde, benzaldehyde, n-undecanol, and/or cetrimonium chloride.   
     
     
         21 . A cosmetic or personal care or house hold, cleaning, Industrial & Institutional product comprising synergistic preservative composition of  claim 1 , and wherein, the amount of said preservative composition is in the range of from about 0.01 wt. % to 5.0 wt. %, relative to the total mass of said products. 
     
     
         22 . A method of killing bacteria, fungi, molds, yeasts and viruses or inhibiting their growth in a cosmetic, personal care, house hold, cleaning, and/or Industrial & Institutional products susceptible to growth of microorganisms comprising incorporating into said products about 0.01 wt. % to 5.0 wt. % of the preservative composition of  claim 1 .